The spotted knapweed, Centaurea maculosa, originates from Europe. It was probably introduced to North America at the end of the 19th century mixed in with alfalfa seeds that were being traded at that time. It has since become an important invasive species in crops causing major financial losses.

To biologists, this species represents an ideal model for understanding the causes and consequences of introducing an exotic plant to a region. The establishment and invasive capacities not only depend on the plant's intrinsic traits (morphology, genotype, reproduction method, toxin production,...), but also on the environmental conditions of the area where it is being introduced. Furthermore, they depend on the species' ability to adapt to its new environment such as, for example, the possible consequences of a change in its ecological niche.

Studying invasive plants in both their place of origin and in the invaded area is necessary in order to determine which biological factors and which environmental changes could have contributed to their successful proliferation. We could then better predict the future distribution of these plants in their new environment.